The invention relates generally to power-driven conveyors and more particularly to conveyor belts with rollers.
Conveyor belts, especially modular plastic conveyor belts, having article-supporting or friction-reducing rollers are used in many conveying applications. The rollers are mounted on axles whose ends are supported in end supports upstanding from an outer belt surface or in the walls of cavities in the body of the belt. The spacing of the end supports or the diameter of the cavities is sufficiently greater than the axial length of the roller to prevent the roller from binding. As the conveyor belt is operated, axial movement of the rollers causes the rollers to bang into the end supports or the cavity walls. In belts with many rollers, the noise of the rollers hitting the hard plastic of the modular conveyor belt can be loud. In transverse roller-top belts, the rollers are aligned across the width of the belt in rows with the axles parallel to the direction of belt travel. All the rollers in a row tend to hit their forward support at the same time at the start of their engagement with the sprockets at the end of the carryway. The regular, loud clicking sound of the rollers as each row rounds the sprockets can be loud enough to reach or exceed OSHA limits for noise (80 dB). And radial motion of the rollers along the carryway can produce a rattling sound.
Thus, there is a need to reduce the noise of rollers in conveyor belts.